초록
Monolithic silica rods of 4mm diameter and 2-5cm length, exhibiting very open and uniform 3D hierarchical pore structure of 35μm flow-through macropores and ca. 20nm mesopores were synthesized using the sol-gel processing combined with pore templating and phase separation. These monoliths were successfully converted into miniaturized multichannel continuous-flow reactors which (for a single rod) could operate at flow rates up to about 20mL/min at backpressure not exceeding 2.5bar. After covalent attachment of invertase, considered as a model enzyme, their potentials were tested in reaction of sucrose hydrolysis and the results were compared, using Michaelis-Menten kinetics, with the performance of mesoporous cellular foam (MCF)-bound invertase immobilized in the same way. The hydrolysis of sucrose appeared to proceed with maximum velocity over 1000 times faster in the monolithic bioreactor than in MCF-based slurry system, and invertase embedded in the mesopores of silica monoliths showed notably larger affinity (lower K<SUB>M</SUB>) to substrate than the native enzyme. The reactors stored at 4<SUP>o</SUP>C retained initial activity for at least 6week and no change in the microreactor performance was seen for at least 2week of continuous operation.